Physics/ Maths question help please

Does anyone know how to and can u please provide worked solutions to all parts of this question please ? I’ve tried for a couple of hours to reach the answer but am truly stumped . Thanks

(edited 6 months ago)

bump

Have you sketched it? You know A+B and B, so sketching those gives an idea about A.

Reply 3

3PiBook

Original post by mqb2766

Have you sketched it? You know A+B and B, so sketching those gives an idea about A.

I tried to sketch but I don’t think I’ve sketched it correct .

Reply 4

mqb2766

Original post by 3PiBook

I tried to sketch but I don’t think I’ve sketched it correct .

Want to upload what you did to check. You have the answer (A) as well as B and A+B in the question so you shouldnt go too wrong.

ii) Then simply says work out A in terms of the x and y componnents by using A = (A+B) - B in both x and y coordinates
iii) Then converts ii) to magnitude angle form

Reply 5

xbqvz

i) I suggest drawing this on axes. You know that AB will ‘end’ at the same point as B, so you can set this to be the origin of your axes (you will know the angles). You can then draw in A to make a triangle. The drawing is the most important part.

ii) Try resolving components here. As AB is resultant, the x components of A and B = the x component of AB (the same for y). Direction is important, so refer to your diagram! You’ll end up with two equations, one with Asin(theta) and one with Acos(theta).

iii) Try to find theta. Dividing Asin(theta) by Acos(theta) will give you an equation with tan(theta). Solve for theta and put this into an equation from before to find |A|.

Let me know if you want me to check your work / explain more thoroughly! :smile: